xref: /linux/virt/kvm/kvm_main.c (revision 7025bec9125b0a02edcaf22c2dce753bf2c95480)
1 /*
2  * Kernel-based Virtual Machine driver for Linux
3  *
4  * This module enables machines with Intel VT-x extensions to run virtual
5  * machines without emulation or binary translation.
6  *
7  * Copyright (C) 2006 Qumranet, Inc.
8  *
9  * Authors:
10  *   Avi Kivity   <avi@qumranet.com>
11  *   Yaniv Kamay  <yaniv@qumranet.com>
12  *
13  * This work is licensed under the terms of the GNU GPL, version 2.  See
14  * the COPYING file in the top-level directory.
15  *
16  */
17 
18 #include "iodev.h"
19 
20 #include <linux/kvm_host.h>
21 #include <linux/kvm.h>
22 #include <linux/module.h>
23 #include <linux/errno.h>
24 #include <linux/percpu.h>
25 #include <linux/gfp.h>
26 #include <linux/mm.h>
27 #include <linux/miscdevice.h>
28 #include <linux/vmalloc.h>
29 #include <linux/reboot.h>
30 #include <linux/debugfs.h>
31 #include <linux/highmem.h>
32 #include <linux/file.h>
33 #include <linux/sysdev.h>
34 #include <linux/cpu.h>
35 #include <linux/sched.h>
36 #include <linux/cpumask.h>
37 #include <linux/smp.h>
38 #include <linux/anon_inodes.h>
39 #include <linux/profile.h>
40 #include <linux/kvm_para.h>
41 #include <linux/pagemap.h>
42 #include <linux/mman.h>
43 #include <linux/swap.h>
44 #include <linux/bitops.h>
45 #include <linux/spinlock.h>
46 #include <linux/compat.h>
47 
48 #include <asm/processor.h>
49 #include <asm/io.h>
50 #include <asm/uaccess.h>
51 #include <asm/pgtable.h>
52 #include <asm-generic/bitops/le.h>
53 
54 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
55 #include "coalesced_mmio.h"
56 #endif
57 
58 #define CREATE_TRACE_POINTS
59 #include <trace/events/kvm.h>
60 
61 MODULE_AUTHOR("Qumranet");
62 MODULE_LICENSE("GPL");
63 
64 /*
65  * Ordering of locks:
66  *
67  * 		kvm->slots_lock --> kvm->lock --> kvm->irq_lock
68  */
69 
70 DEFINE_SPINLOCK(kvm_lock);
71 LIST_HEAD(vm_list);
72 
73 static cpumask_var_t cpus_hardware_enabled;
74 static int kvm_usage_count = 0;
75 static atomic_t hardware_enable_failed;
76 
77 struct kmem_cache *kvm_vcpu_cache;
78 EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
79 
80 static __read_mostly struct preempt_ops kvm_preempt_ops;
81 
82 struct dentry *kvm_debugfs_dir;
83 
84 static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
85 			   unsigned long arg);
86 static int hardware_enable_all(void);
87 static void hardware_disable_all(void);
88 
89 static bool kvm_rebooting;
90 
91 static bool largepages_enabled = true;
92 
93 inline int kvm_is_mmio_pfn(pfn_t pfn)
94 {
95 	if (pfn_valid(pfn)) {
96 		struct page *page = compound_head(pfn_to_page(pfn));
97 		return PageReserved(page);
98 	}
99 
100 	return true;
101 }
102 
103 /*
104  * Switches to specified vcpu, until a matching vcpu_put()
105  */
106 void vcpu_load(struct kvm_vcpu *vcpu)
107 {
108 	int cpu;
109 
110 	mutex_lock(&vcpu->mutex);
111 	cpu = get_cpu();
112 	preempt_notifier_register(&vcpu->preempt_notifier);
113 	kvm_arch_vcpu_load(vcpu, cpu);
114 	put_cpu();
115 }
116 
117 void vcpu_put(struct kvm_vcpu *vcpu)
118 {
119 	preempt_disable();
120 	kvm_arch_vcpu_put(vcpu);
121 	preempt_notifier_unregister(&vcpu->preempt_notifier);
122 	preempt_enable();
123 	mutex_unlock(&vcpu->mutex);
124 }
125 
126 static void ack_flush(void *_completed)
127 {
128 }
129 
130 static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
131 {
132 	int i, cpu, me;
133 	cpumask_var_t cpus;
134 	bool called = true;
135 	struct kvm_vcpu *vcpu;
136 
137 	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
138 
139 	spin_lock(&kvm->requests_lock);
140 	me = smp_processor_id();
141 	kvm_for_each_vcpu(i, vcpu, kvm) {
142 		if (test_and_set_bit(req, &vcpu->requests))
143 			continue;
144 		cpu = vcpu->cpu;
145 		if (cpus != NULL && cpu != -1 && cpu != me)
146 			cpumask_set_cpu(cpu, cpus);
147 	}
148 	if (unlikely(cpus == NULL))
149 		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
150 	else if (!cpumask_empty(cpus))
151 		smp_call_function_many(cpus, ack_flush, NULL, 1);
152 	else
153 		called = false;
154 	spin_unlock(&kvm->requests_lock);
155 	free_cpumask_var(cpus);
156 	return called;
157 }
158 
159 void kvm_flush_remote_tlbs(struct kvm *kvm)
160 {
161 	if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
162 		++kvm->stat.remote_tlb_flush;
163 }
164 
165 void kvm_reload_remote_mmus(struct kvm *kvm)
166 {
167 	make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
168 }
169 
170 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
171 {
172 	struct page *page;
173 	int r;
174 
175 	mutex_init(&vcpu->mutex);
176 	vcpu->cpu = -1;
177 	vcpu->kvm = kvm;
178 	vcpu->vcpu_id = id;
179 	init_waitqueue_head(&vcpu->wq);
180 
181 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
182 	if (!page) {
183 		r = -ENOMEM;
184 		goto fail;
185 	}
186 	vcpu->run = page_address(page);
187 
188 	r = kvm_arch_vcpu_init(vcpu);
189 	if (r < 0)
190 		goto fail_free_run;
191 	return 0;
192 
193 fail_free_run:
194 	free_page((unsigned long)vcpu->run);
195 fail:
196 	return r;
197 }
198 EXPORT_SYMBOL_GPL(kvm_vcpu_init);
199 
200 void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
201 {
202 	kvm_arch_vcpu_uninit(vcpu);
203 	free_page((unsigned long)vcpu->run);
204 }
205 EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
206 
207 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
208 static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
209 {
210 	return container_of(mn, struct kvm, mmu_notifier);
211 }
212 
213 static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
214 					     struct mm_struct *mm,
215 					     unsigned long address)
216 {
217 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
218 	int need_tlb_flush;
219 
220 	/*
221 	 * When ->invalidate_page runs, the linux pte has been zapped
222 	 * already but the page is still allocated until
223 	 * ->invalidate_page returns. So if we increase the sequence
224 	 * here the kvm page fault will notice if the spte can't be
225 	 * established because the page is going to be freed. If
226 	 * instead the kvm page fault establishes the spte before
227 	 * ->invalidate_page runs, kvm_unmap_hva will release it
228 	 * before returning.
229 	 *
230 	 * The sequence increase only need to be seen at spin_unlock
231 	 * time, and not at spin_lock time.
232 	 *
233 	 * Increasing the sequence after the spin_unlock would be
234 	 * unsafe because the kvm page fault could then establish the
235 	 * pte after kvm_unmap_hva returned, without noticing the page
236 	 * is going to be freed.
237 	 */
238 	spin_lock(&kvm->mmu_lock);
239 	kvm->mmu_notifier_seq++;
240 	need_tlb_flush = kvm_unmap_hva(kvm, address);
241 	spin_unlock(&kvm->mmu_lock);
242 
243 	/* we've to flush the tlb before the pages can be freed */
244 	if (need_tlb_flush)
245 		kvm_flush_remote_tlbs(kvm);
246 
247 }
248 
249 static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
250 					struct mm_struct *mm,
251 					unsigned long address,
252 					pte_t pte)
253 {
254 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
255 
256 	spin_lock(&kvm->mmu_lock);
257 	kvm->mmu_notifier_seq++;
258 	kvm_set_spte_hva(kvm, address, pte);
259 	spin_unlock(&kvm->mmu_lock);
260 }
261 
262 static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
263 						    struct mm_struct *mm,
264 						    unsigned long start,
265 						    unsigned long end)
266 {
267 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
268 	int need_tlb_flush = 0;
269 
270 	spin_lock(&kvm->mmu_lock);
271 	/*
272 	 * The count increase must become visible at unlock time as no
273 	 * spte can be established without taking the mmu_lock and
274 	 * count is also read inside the mmu_lock critical section.
275 	 */
276 	kvm->mmu_notifier_count++;
277 	for (; start < end; start += PAGE_SIZE)
278 		need_tlb_flush |= kvm_unmap_hva(kvm, start);
279 	spin_unlock(&kvm->mmu_lock);
280 
281 	/* we've to flush the tlb before the pages can be freed */
282 	if (need_tlb_flush)
283 		kvm_flush_remote_tlbs(kvm);
284 }
285 
286 static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
287 						  struct mm_struct *mm,
288 						  unsigned long start,
289 						  unsigned long end)
290 {
291 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
292 
293 	spin_lock(&kvm->mmu_lock);
294 	/*
295 	 * This sequence increase will notify the kvm page fault that
296 	 * the page that is going to be mapped in the spte could have
297 	 * been freed.
298 	 */
299 	kvm->mmu_notifier_seq++;
300 	/*
301 	 * The above sequence increase must be visible before the
302 	 * below count decrease but both values are read by the kvm
303 	 * page fault under mmu_lock spinlock so we don't need to add
304 	 * a smb_wmb() here in between the two.
305 	 */
306 	kvm->mmu_notifier_count--;
307 	spin_unlock(&kvm->mmu_lock);
308 
309 	BUG_ON(kvm->mmu_notifier_count < 0);
310 }
311 
312 static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
313 					      struct mm_struct *mm,
314 					      unsigned long address)
315 {
316 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
317 	int young;
318 
319 	spin_lock(&kvm->mmu_lock);
320 	young = kvm_age_hva(kvm, address);
321 	spin_unlock(&kvm->mmu_lock);
322 
323 	if (young)
324 		kvm_flush_remote_tlbs(kvm);
325 
326 	return young;
327 }
328 
329 static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
330 				     struct mm_struct *mm)
331 {
332 	struct kvm *kvm = mmu_notifier_to_kvm(mn);
333 	kvm_arch_flush_shadow(kvm);
334 }
335 
336 static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
337 	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
338 	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
339 	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
340 	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
341 	.change_pte		= kvm_mmu_notifier_change_pte,
342 	.release		= kvm_mmu_notifier_release,
343 };
344 #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
345 
346 static struct kvm *kvm_create_vm(void)
347 {
348 	int r = 0;
349 	struct kvm *kvm = kvm_arch_create_vm();
350 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
351 	struct page *page;
352 #endif
353 
354 	if (IS_ERR(kvm))
355 		goto out;
356 
357 	r = hardware_enable_all();
358 	if (r)
359 		goto out_err_nodisable;
360 
361 #ifdef CONFIG_HAVE_KVM_IRQCHIP
362 	INIT_HLIST_HEAD(&kvm->mask_notifier_list);
363 	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
364 #endif
365 
366 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
367 	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
368 	if (!page) {
369 		r = -ENOMEM;
370 		goto out_err;
371 	}
372 	kvm->coalesced_mmio_ring =
373 			(struct kvm_coalesced_mmio_ring *)page_address(page);
374 #endif
375 
376 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
377 	{
378 		kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
379 		r = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
380 		if (r) {
381 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
382 			put_page(page);
383 #endif
384 			goto out_err;
385 		}
386 	}
387 #endif
388 
389 	kvm->mm = current->mm;
390 	atomic_inc(&kvm->mm->mm_count);
391 	spin_lock_init(&kvm->mmu_lock);
392 	spin_lock_init(&kvm->requests_lock);
393 	kvm_io_bus_init(&kvm->pio_bus);
394 	kvm_eventfd_init(kvm);
395 	mutex_init(&kvm->lock);
396 	mutex_init(&kvm->irq_lock);
397 	kvm_io_bus_init(&kvm->mmio_bus);
398 	init_rwsem(&kvm->slots_lock);
399 	atomic_set(&kvm->users_count, 1);
400 	spin_lock(&kvm_lock);
401 	list_add(&kvm->vm_list, &vm_list);
402 	spin_unlock(&kvm_lock);
403 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
404 	kvm_coalesced_mmio_init(kvm);
405 #endif
406 out:
407 	return kvm;
408 
409 out_err:
410 	hardware_disable_all();
411 out_err_nodisable:
412 	kfree(kvm);
413 	return ERR_PTR(r);
414 }
415 
416 /*
417  * Free any memory in @free but not in @dont.
418  */
419 static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
420 				  struct kvm_memory_slot *dont)
421 {
422 	int i;
423 
424 	if (!dont || free->rmap != dont->rmap)
425 		vfree(free->rmap);
426 
427 	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
428 		vfree(free->dirty_bitmap);
429 
430 
431 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
432 		if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
433 			vfree(free->lpage_info[i]);
434 			free->lpage_info[i] = NULL;
435 		}
436 	}
437 
438 	free->npages = 0;
439 	free->dirty_bitmap = NULL;
440 	free->rmap = NULL;
441 }
442 
443 void kvm_free_physmem(struct kvm *kvm)
444 {
445 	int i;
446 
447 	for (i = 0; i < kvm->nmemslots; ++i)
448 		kvm_free_physmem_slot(&kvm->memslots[i], NULL);
449 }
450 
451 static void kvm_destroy_vm(struct kvm *kvm)
452 {
453 	struct mm_struct *mm = kvm->mm;
454 
455 	kvm_arch_sync_events(kvm);
456 	spin_lock(&kvm_lock);
457 	list_del(&kvm->vm_list);
458 	spin_unlock(&kvm_lock);
459 	kvm_free_irq_routing(kvm);
460 	kvm_io_bus_destroy(&kvm->pio_bus);
461 	kvm_io_bus_destroy(&kvm->mmio_bus);
462 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
463 	if (kvm->coalesced_mmio_ring != NULL)
464 		free_page((unsigned long)kvm->coalesced_mmio_ring);
465 #endif
466 #if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
467 	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
468 #else
469 	kvm_arch_flush_shadow(kvm);
470 #endif
471 	kvm_arch_destroy_vm(kvm);
472 	hardware_disable_all();
473 	mmdrop(mm);
474 }
475 
476 void kvm_get_kvm(struct kvm *kvm)
477 {
478 	atomic_inc(&kvm->users_count);
479 }
480 EXPORT_SYMBOL_GPL(kvm_get_kvm);
481 
482 void kvm_put_kvm(struct kvm *kvm)
483 {
484 	if (atomic_dec_and_test(&kvm->users_count))
485 		kvm_destroy_vm(kvm);
486 }
487 EXPORT_SYMBOL_GPL(kvm_put_kvm);
488 
489 
490 static int kvm_vm_release(struct inode *inode, struct file *filp)
491 {
492 	struct kvm *kvm = filp->private_data;
493 
494 	kvm_irqfd_release(kvm);
495 
496 	kvm_put_kvm(kvm);
497 	return 0;
498 }
499 
500 /*
501  * Allocate some memory and give it an address in the guest physical address
502  * space.
503  *
504  * Discontiguous memory is allowed, mostly for framebuffers.
505  *
506  * Must be called holding mmap_sem for write.
507  */
508 int __kvm_set_memory_region(struct kvm *kvm,
509 			    struct kvm_userspace_memory_region *mem,
510 			    int user_alloc)
511 {
512 	int r;
513 	gfn_t base_gfn;
514 	unsigned long npages;
515 	unsigned long i;
516 	struct kvm_memory_slot *memslot;
517 	struct kvm_memory_slot old, new;
518 
519 	r = -EINVAL;
520 	/* General sanity checks */
521 	if (mem->memory_size & (PAGE_SIZE - 1))
522 		goto out;
523 	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
524 		goto out;
525 	if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
526 		goto out;
527 	if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
528 		goto out;
529 	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
530 		goto out;
531 
532 	memslot = &kvm->memslots[mem->slot];
533 	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
534 	npages = mem->memory_size >> PAGE_SHIFT;
535 
536 	if (!npages)
537 		mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
538 
539 	new = old = *memslot;
540 
541 	new.base_gfn = base_gfn;
542 	new.npages = npages;
543 	new.flags = mem->flags;
544 
545 	/* Disallow changing a memory slot's size. */
546 	r = -EINVAL;
547 	if (npages && old.npages && npages != old.npages)
548 		goto out_free;
549 
550 	/* Check for overlaps */
551 	r = -EEXIST;
552 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
553 		struct kvm_memory_slot *s = &kvm->memslots[i];
554 
555 		if (s == memslot || !s->npages)
556 			continue;
557 		if (!((base_gfn + npages <= s->base_gfn) ||
558 		      (base_gfn >= s->base_gfn + s->npages)))
559 			goto out_free;
560 	}
561 
562 	/* Free page dirty bitmap if unneeded */
563 	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
564 		new.dirty_bitmap = NULL;
565 
566 	r = -ENOMEM;
567 
568 	/* Allocate if a slot is being created */
569 #ifndef CONFIG_S390
570 	if (npages && !new.rmap) {
571 		new.rmap = vmalloc(npages * sizeof(struct page *));
572 
573 		if (!new.rmap)
574 			goto out_free;
575 
576 		memset(new.rmap, 0, npages * sizeof(*new.rmap));
577 
578 		new.user_alloc = user_alloc;
579 		/*
580 		 * hva_to_rmmap() serialzies with the mmu_lock and to be
581 		 * safe it has to ignore memslots with !user_alloc &&
582 		 * !userspace_addr.
583 		 */
584 		if (user_alloc)
585 			new.userspace_addr = mem->userspace_addr;
586 		else
587 			new.userspace_addr = 0;
588 	}
589 	if (!npages)
590 		goto skip_lpage;
591 
592 	for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
593 		unsigned long ugfn;
594 		unsigned long j;
595 		int lpages;
596 		int level = i + 2;
597 
598 		/* Avoid unused variable warning if no large pages */
599 		(void)level;
600 
601 		if (new.lpage_info[i])
602 			continue;
603 
604 		lpages = 1 + (base_gfn + npages - 1) /
605 			     KVM_PAGES_PER_HPAGE(level);
606 		lpages -= base_gfn / KVM_PAGES_PER_HPAGE(level);
607 
608 		new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
609 
610 		if (!new.lpage_info[i])
611 			goto out_free;
612 
613 		memset(new.lpage_info[i], 0,
614 		       lpages * sizeof(*new.lpage_info[i]));
615 
616 		if (base_gfn % KVM_PAGES_PER_HPAGE(level))
617 			new.lpage_info[i][0].write_count = 1;
618 		if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE(level))
619 			new.lpage_info[i][lpages - 1].write_count = 1;
620 		ugfn = new.userspace_addr >> PAGE_SHIFT;
621 		/*
622 		 * If the gfn and userspace address are not aligned wrt each
623 		 * other, or if explicitly asked to, disable large page
624 		 * support for this slot
625 		 */
626 		if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
627 		    !largepages_enabled)
628 			for (j = 0; j < lpages; ++j)
629 				new.lpage_info[i][j].write_count = 1;
630 	}
631 
632 skip_lpage:
633 
634 	/* Allocate page dirty bitmap if needed */
635 	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
636 		unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
637 
638 		new.dirty_bitmap = vmalloc(dirty_bytes);
639 		if (!new.dirty_bitmap)
640 			goto out_free;
641 		memset(new.dirty_bitmap, 0, dirty_bytes);
642 		if (old.npages)
643 			kvm_arch_flush_shadow(kvm);
644 	}
645 #else  /* not defined CONFIG_S390 */
646 	new.user_alloc = user_alloc;
647 	if (user_alloc)
648 		new.userspace_addr = mem->userspace_addr;
649 #endif /* not defined CONFIG_S390 */
650 
651 	if (!npages)
652 		kvm_arch_flush_shadow(kvm);
653 
654 	spin_lock(&kvm->mmu_lock);
655 	if (mem->slot >= kvm->nmemslots)
656 		kvm->nmemslots = mem->slot + 1;
657 
658 	*memslot = new;
659 	spin_unlock(&kvm->mmu_lock);
660 
661 	r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
662 	if (r) {
663 		spin_lock(&kvm->mmu_lock);
664 		*memslot = old;
665 		spin_unlock(&kvm->mmu_lock);
666 		goto out_free;
667 	}
668 
669 	kvm_free_physmem_slot(&old, npages ? &new : NULL);
670 	/* Slot deletion case: we have to update the current slot */
671 	spin_lock(&kvm->mmu_lock);
672 	if (!npages)
673 		*memslot = old;
674 	spin_unlock(&kvm->mmu_lock);
675 #ifdef CONFIG_DMAR
676 	/* map the pages in iommu page table */
677 	r = kvm_iommu_map_pages(kvm, base_gfn, npages);
678 	if (r)
679 		goto out;
680 #endif
681 	return 0;
682 
683 out_free:
684 	kvm_free_physmem_slot(&new, &old);
685 out:
686 	return r;
687 
688 }
689 EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
690 
691 int kvm_set_memory_region(struct kvm *kvm,
692 			  struct kvm_userspace_memory_region *mem,
693 			  int user_alloc)
694 {
695 	int r;
696 
697 	down_write(&kvm->slots_lock);
698 	r = __kvm_set_memory_region(kvm, mem, user_alloc);
699 	up_write(&kvm->slots_lock);
700 	return r;
701 }
702 EXPORT_SYMBOL_GPL(kvm_set_memory_region);
703 
704 int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
705 				   struct
706 				   kvm_userspace_memory_region *mem,
707 				   int user_alloc)
708 {
709 	if (mem->slot >= KVM_MEMORY_SLOTS)
710 		return -EINVAL;
711 	return kvm_set_memory_region(kvm, mem, user_alloc);
712 }
713 
714 int kvm_get_dirty_log(struct kvm *kvm,
715 			struct kvm_dirty_log *log, int *is_dirty)
716 {
717 	struct kvm_memory_slot *memslot;
718 	int r, i;
719 	int n;
720 	unsigned long any = 0;
721 
722 	r = -EINVAL;
723 	if (log->slot >= KVM_MEMORY_SLOTS)
724 		goto out;
725 
726 	memslot = &kvm->memslots[log->slot];
727 	r = -ENOENT;
728 	if (!memslot->dirty_bitmap)
729 		goto out;
730 
731 	n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
732 
733 	for (i = 0; !any && i < n/sizeof(long); ++i)
734 		any = memslot->dirty_bitmap[i];
735 
736 	r = -EFAULT;
737 	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
738 		goto out;
739 
740 	if (any)
741 		*is_dirty = 1;
742 
743 	r = 0;
744 out:
745 	return r;
746 }
747 
748 void kvm_disable_largepages(void)
749 {
750 	largepages_enabled = false;
751 }
752 EXPORT_SYMBOL_GPL(kvm_disable_largepages);
753 
754 int is_error_page(struct page *page)
755 {
756 	return page == bad_page;
757 }
758 EXPORT_SYMBOL_GPL(is_error_page);
759 
760 int is_error_pfn(pfn_t pfn)
761 {
762 	return pfn == bad_pfn;
763 }
764 EXPORT_SYMBOL_GPL(is_error_pfn);
765 
766 static inline unsigned long bad_hva(void)
767 {
768 	return PAGE_OFFSET;
769 }
770 
771 int kvm_is_error_hva(unsigned long addr)
772 {
773 	return addr == bad_hva();
774 }
775 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
776 
777 struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
778 {
779 	int i;
780 
781 	for (i = 0; i < kvm->nmemslots; ++i) {
782 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
783 
784 		if (gfn >= memslot->base_gfn
785 		    && gfn < memslot->base_gfn + memslot->npages)
786 			return memslot;
787 	}
788 	return NULL;
789 }
790 EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased);
791 
792 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
793 {
794 	gfn = unalias_gfn(kvm, gfn);
795 	return gfn_to_memslot_unaliased(kvm, gfn);
796 }
797 
798 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
799 {
800 	int i;
801 
802 	gfn = unalias_gfn(kvm, gfn);
803 	for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
804 		struct kvm_memory_slot *memslot = &kvm->memslots[i];
805 
806 		if (gfn >= memslot->base_gfn
807 		    && gfn < memslot->base_gfn + memslot->npages)
808 			return 1;
809 	}
810 	return 0;
811 }
812 EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
813 
814 unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
815 {
816 	struct kvm_memory_slot *slot;
817 
818 	gfn = unalias_gfn(kvm, gfn);
819 	slot = gfn_to_memslot_unaliased(kvm, gfn);
820 	if (!slot)
821 		return bad_hva();
822 	return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
823 }
824 EXPORT_SYMBOL_GPL(gfn_to_hva);
825 
826 pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
827 {
828 	struct page *page[1];
829 	unsigned long addr;
830 	int npages;
831 	pfn_t pfn;
832 
833 	might_sleep();
834 
835 	addr = gfn_to_hva(kvm, gfn);
836 	if (kvm_is_error_hva(addr)) {
837 		get_page(bad_page);
838 		return page_to_pfn(bad_page);
839 	}
840 
841 	npages = get_user_pages_fast(addr, 1, 1, page);
842 
843 	if (unlikely(npages != 1)) {
844 		struct vm_area_struct *vma;
845 
846 		down_read(&current->mm->mmap_sem);
847 		vma = find_vma(current->mm, addr);
848 
849 		if (vma == NULL || addr < vma->vm_start ||
850 		    !(vma->vm_flags & VM_PFNMAP)) {
851 			up_read(&current->mm->mmap_sem);
852 			get_page(bad_page);
853 			return page_to_pfn(bad_page);
854 		}
855 
856 		pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
857 		up_read(&current->mm->mmap_sem);
858 		BUG_ON(!kvm_is_mmio_pfn(pfn));
859 	} else
860 		pfn = page_to_pfn(page[0]);
861 
862 	return pfn;
863 }
864 
865 EXPORT_SYMBOL_GPL(gfn_to_pfn);
866 
867 struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
868 {
869 	pfn_t pfn;
870 
871 	pfn = gfn_to_pfn(kvm, gfn);
872 	if (!kvm_is_mmio_pfn(pfn))
873 		return pfn_to_page(pfn);
874 
875 	WARN_ON(kvm_is_mmio_pfn(pfn));
876 
877 	get_page(bad_page);
878 	return bad_page;
879 }
880 
881 EXPORT_SYMBOL_GPL(gfn_to_page);
882 
883 void kvm_release_page_clean(struct page *page)
884 {
885 	kvm_release_pfn_clean(page_to_pfn(page));
886 }
887 EXPORT_SYMBOL_GPL(kvm_release_page_clean);
888 
889 void kvm_release_pfn_clean(pfn_t pfn)
890 {
891 	if (!kvm_is_mmio_pfn(pfn))
892 		put_page(pfn_to_page(pfn));
893 }
894 EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
895 
896 void kvm_release_page_dirty(struct page *page)
897 {
898 	kvm_release_pfn_dirty(page_to_pfn(page));
899 }
900 EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
901 
902 void kvm_release_pfn_dirty(pfn_t pfn)
903 {
904 	kvm_set_pfn_dirty(pfn);
905 	kvm_release_pfn_clean(pfn);
906 }
907 EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
908 
909 void kvm_set_page_dirty(struct page *page)
910 {
911 	kvm_set_pfn_dirty(page_to_pfn(page));
912 }
913 EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
914 
915 void kvm_set_pfn_dirty(pfn_t pfn)
916 {
917 	if (!kvm_is_mmio_pfn(pfn)) {
918 		struct page *page = pfn_to_page(pfn);
919 		if (!PageReserved(page))
920 			SetPageDirty(page);
921 	}
922 }
923 EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
924 
925 void kvm_set_pfn_accessed(pfn_t pfn)
926 {
927 	if (!kvm_is_mmio_pfn(pfn))
928 		mark_page_accessed(pfn_to_page(pfn));
929 }
930 EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
931 
932 void kvm_get_pfn(pfn_t pfn)
933 {
934 	if (!kvm_is_mmio_pfn(pfn))
935 		get_page(pfn_to_page(pfn));
936 }
937 EXPORT_SYMBOL_GPL(kvm_get_pfn);
938 
939 static int next_segment(unsigned long len, int offset)
940 {
941 	if (len > PAGE_SIZE - offset)
942 		return PAGE_SIZE - offset;
943 	else
944 		return len;
945 }
946 
947 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
948 			int len)
949 {
950 	int r;
951 	unsigned long addr;
952 
953 	addr = gfn_to_hva(kvm, gfn);
954 	if (kvm_is_error_hva(addr))
955 		return -EFAULT;
956 	r = copy_from_user(data, (void __user *)addr + offset, len);
957 	if (r)
958 		return -EFAULT;
959 	return 0;
960 }
961 EXPORT_SYMBOL_GPL(kvm_read_guest_page);
962 
963 int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
964 {
965 	gfn_t gfn = gpa >> PAGE_SHIFT;
966 	int seg;
967 	int offset = offset_in_page(gpa);
968 	int ret;
969 
970 	while ((seg = next_segment(len, offset)) != 0) {
971 		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
972 		if (ret < 0)
973 			return ret;
974 		offset = 0;
975 		len -= seg;
976 		data += seg;
977 		++gfn;
978 	}
979 	return 0;
980 }
981 EXPORT_SYMBOL_GPL(kvm_read_guest);
982 
983 int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
984 			  unsigned long len)
985 {
986 	int r;
987 	unsigned long addr;
988 	gfn_t gfn = gpa >> PAGE_SHIFT;
989 	int offset = offset_in_page(gpa);
990 
991 	addr = gfn_to_hva(kvm, gfn);
992 	if (kvm_is_error_hva(addr))
993 		return -EFAULT;
994 	pagefault_disable();
995 	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
996 	pagefault_enable();
997 	if (r)
998 		return -EFAULT;
999 	return 0;
1000 }
1001 EXPORT_SYMBOL(kvm_read_guest_atomic);
1002 
1003 int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
1004 			 int offset, int len)
1005 {
1006 	int r;
1007 	unsigned long addr;
1008 
1009 	addr = gfn_to_hva(kvm, gfn);
1010 	if (kvm_is_error_hva(addr))
1011 		return -EFAULT;
1012 	r = copy_to_user((void __user *)addr + offset, data, len);
1013 	if (r)
1014 		return -EFAULT;
1015 	mark_page_dirty(kvm, gfn);
1016 	return 0;
1017 }
1018 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
1019 
1020 int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
1021 		    unsigned long len)
1022 {
1023 	gfn_t gfn = gpa >> PAGE_SHIFT;
1024 	int seg;
1025 	int offset = offset_in_page(gpa);
1026 	int ret;
1027 
1028 	while ((seg = next_segment(len, offset)) != 0) {
1029 		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
1030 		if (ret < 0)
1031 			return ret;
1032 		offset = 0;
1033 		len -= seg;
1034 		data += seg;
1035 		++gfn;
1036 	}
1037 	return 0;
1038 }
1039 
1040 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
1041 {
1042 	return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
1043 }
1044 EXPORT_SYMBOL_GPL(kvm_clear_guest_page);
1045 
1046 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
1047 {
1048 	gfn_t gfn = gpa >> PAGE_SHIFT;
1049 	int seg;
1050 	int offset = offset_in_page(gpa);
1051 	int ret;
1052 
1053         while ((seg = next_segment(len, offset)) != 0) {
1054 		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
1055 		if (ret < 0)
1056 			return ret;
1057 		offset = 0;
1058 		len -= seg;
1059 		++gfn;
1060 	}
1061 	return 0;
1062 }
1063 EXPORT_SYMBOL_GPL(kvm_clear_guest);
1064 
1065 void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
1066 {
1067 	struct kvm_memory_slot *memslot;
1068 
1069 	gfn = unalias_gfn(kvm, gfn);
1070 	memslot = gfn_to_memslot_unaliased(kvm, gfn);
1071 	if (memslot && memslot->dirty_bitmap) {
1072 		unsigned long rel_gfn = gfn - memslot->base_gfn;
1073 
1074 		/* avoid RMW */
1075 		if (!generic_test_le_bit(rel_gfn, memslot->dirty_bitmap))
1076 			generic___set_le_bit(rel_gfn, memslot->dirty_bitmap);
1077 	}
1078 }
1079 
1080 /*
1081  * The vCPU has executed a HLT instruction with in-kernel mode enabled.
1082  */
1083 void kvm_vcpu_block(struct kvm_vcpu *vcpu)
1084 {
1085 	DEFINE_WAIT(wait);
1086 
1087 	for (;;) {
1088 		prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1089 
1090 		if (kvm_arch_vcpu_runnable(vcpu)) {
1091 			set_bit(KVM_REQ_UNHALT, &vcpu->requests);
1092 			break;
1093 		}
1094 		if (kvm_cpu_has_pending_timer(vcpu))
1095 			break;
1096 		if (signal_pending(current))
1097 			break;
1098 
1099 		schedule();
1100 	}
1101 
1102 	finish_wait(&vcpu->wq, &wait);
1103 }
1104 
1105 void kvm_resched(struct kvm_vcpu *vcpu)
1106 {
1107 	if (!need_resched())
1108 		return;
1109 	cond_resched();
1110 }
1111 EXPORT_SYMBOL_GPL(kvm_resched);
1112 
1113 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu)
1114 {
1115 	ktime_t expires;
1116 	DEFINE_WAIT(wait);
1117 
1118 	prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
1119 
1120 	/* Sleep for 100 us, and hope lock-holder got scheduled */
1121 	expires = ktime_add_ns(ktime_get(), 100000UL);
1122 	schedule_hrtimeout(&expires, HRTIMER_MODE_ABS);
1123 
1124 	finish_wait(&vcpu->wq, &wait);
1125 }
1126 EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
1127 
1128 static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1129 {
1130 	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
1131 	struct page *page;
1132 
1133 	if (vmf->pgoff == 0)
1134 		page = virt_to_page(vcpu->run);
1135 #ifdef CONFIG_X86
1136 	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
1137 		page = virt_to_page(vcpu->arch.pio_data);
1138 #endif
1139 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1140 	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
1141 		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
1142 #endif
1143 	else
1144 		return VM_FAULT_SIGBUS;
1145 	get_page(page);
1146 	vmf->page = page;
1147 	return 0;
1148 }
1149 
1150 static const struct vm_operations_struct kvm_vcpu_vm_ops = {
1151 	.fault = kvm_vcpu_fault,
1152 };
1153 
1154 static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
1155 {
1156 	vma->vm_ops = &kvm_vcpu_vm_ops;
1157 	return 0;
1158 }
1159 
1160 static int kvm_vcpu_release(struct inode *inode, struct file *filp)
1161 {
1162 	struct kvm_vcpu *vcpu = filp->private_data;
1163 
1164 	kvm_put_kvm(vcpu->kvm);
1165 	return 0;
1166 }
1167 
1168 static struct file_operations kvm_vcpu_fops = {
1169 	.release        = kvm_vcpu_release,
1170 	.unlocked_ioctl = kvm_vcpu_ioctl,
1171 	.compat_ioctl   = kvm_vcpu_ioctl,
1172 	.mmap           = kvm_vcpu_mmap,
1173 };
1174 
1175 /*
1176  * Allocates an inode for the vcpu.
1177  */
1178 static int create_vcpu_fd(struct kvm_vcpu *vcpu)
1179 {
1180 	return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, 0);
1181 }
1182 
1183 /*
1184  * Creates some virtual cpus.  Good luck creating more than one.
1185  */
1186 static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
1187 {
1188 	int r;
1189 	struct kvm_vcpu *vcpu, *v;
1190 
1191 	vcpu = kvm_arch_vcpu_create(kvm, id);
1192 	if (IS_ERR(vcpu))
1193 		return PTR_ERR(vcpu);
1194 
1195 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
1196 
1197 	r = kvm_arch_vcpu_setup(vcpu);
1198 	if (r)
1199 		return r;
1200 
1201 	mutex_lock(&kvm->lock);
1202 	if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
1203 		r = -EINVAL;
1204 		goto vcpu_destroy;
1205 	}
1206 
1207 	kvm_for_each_vcpu(r, v, kvm)
1208 		if (v->vcpu_id == id) {
1209 			r = -EEXIST;
1210 			goto vcpu_destroy;
1211 		}
1212 
1213 	BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
1214 
1215 	/* Now it's all set up, let userspace reach it */
1216 	kvm_get_kvm(kvm);
1217 	r = create_vcpu_fd(vcpu);
1218 	if (r < 0) {
1219 		kvm_put_kvm(kvm);
1220 		goto vcpu_destroy;
1221 	}
1222 
1223 	kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
1224 	smp_wmb();
1225 	atomic_inc(&kvm->online_vcpus);
1226 
1227 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1228 	if (kvm->bsp_vcpu_id == id)
1229 		kvm->bsp_vcpu = vcpu;
1230 #endif
1231 	mutex_unlock(&kvm->lock);
1232 	return r;
1233 
1234 vcpu_destroy:
1235 	mutex_unlock(&kvm->lock);
1236 	kvm_arch_vcpu_destroy(vcpu);
1237 	return r;
1238 }
1239 
1240 static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
1241 {
1242 	if (sigset) {
1243 		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
1244 		vcpu->sigset_active = 1;
1245 		vcpu->sigset = *sigset;
1246 	} else
1247 		vcpu->sigset_active = 0;
1248 	return 0;
1249 }
1250 
1251 static long kvm_vcpu_ioctl(struct file *filp,
1252 			   unsigned int ioctl, unsigned long arg)
1253 {
1254 	struct kvm_vcpu *vcpu = filp->private_data;
1255 	void __user *argp = (void __user *)arg;
1256 	int r;
1257 	struct kvm_fpu *fpu = NULL;
1258 	struct kvm_sregs *kvm_sregs = NULL;
1259 
1260 	if (vcpu->kvm->mm != current->mm)
1261 		return -EIO;
1262 	switch (ioctl) {
1263 	case KVM_RUN:
1264 		r = -EINVAL;
1265 		if (arg)
1266 			goto out;
1267 		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
1268 		break;
1269 	case KVM_GET_REGS: {
1270 		struct kvm_regs *kvm_regs;
1271 
1272 		r = -ENOMEM;
1273 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1274 		if (!kvm_regs)
1275 			goto out;
1276 		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
1277 		if (r)
1278 			goto out_free1;
1279 		r = -EFAULT;
1280 		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
1281 			goto out_free1;
1282 		r = 0;
1283 out_free1:
1284 		kfree(kvm_regs);
1285 		break;
1286 	}
1287 	case KVM_SET_REGS: {
1288 		struct kvm_regs *kvm_regs;
1289 
1290 		r = -ENOMEM;
1291 		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
1292 		if (!kvm_regs)
1293 			goto out;
1294 		r = -EFAULT;
1295 		if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
1296 			goto out_free2;
1297 		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
1298 		if (r)
1299 			goto out_free2;
1300 		r = 0;
1301 out_free2:
1302 		kfree(kvm_regs);
1303 		break;
1304 	}
1305 	case KVM_GET_SREGS: {
1306 		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1307 		r = -ENOMEM;
1308 		if (!kvm_sregs)
1309 			goto out;
1310 		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
1311 		if (r)
1312 			goto out;
1313 		r = -EFAULT;
1314 		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
1315 			goto out;
1316 		r = 0;
1317 		break;
1318 	}
1319 	case KVM_SET_SREGS: {
1320 		kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
1321 		r = -ENOMEM;
1322 		if (!kvm_sregs)
1323 			goto out;
1324 		r = -EFAULT;
1325 		if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
1326 			goto out;
1327 		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
1328 		if (r)
1329 			goto out;
1330 		r = 0;
1331 		break;
1332 	}
1333 	case KVM_GET_MP_STATE: {
1334 		struct kvm_mp_state mp_state;
1335 
1336 		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
1337 		if (r)
1338 			goto out;
1339 		r = -EFAULT;
1340 		if (copy_to_user(argp, &mp_state, sizeof mp_state))
1341 			goto out;
1342 		r = 0;
1343 		break;
1344 	}
1345 	case KVM_SET_MP_STATE: {
1346 		struct kvm_mp_state mp_state;
1347 
1348 		r = -EFAULT;
1349 		if (copy_from_user(&mp_state, argp, sizeof mp_state))
1350 			goto out;
1351 		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
1352 		if (r)
1353 			goto out;
1354 		r = 0;
1355 		break;
1356 	}
1357 	case KVM_TRANSLATE: {
1358 		struct kvm_translation tr;
1359 
1360 		r = -EFAULT;
1361 		if (copy_from_user(&tr, argp, sizeof tr))
1362 			goto out;
1363 		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
1364 		if (r)
1365 			goto out;
1366 		r = -EFAULT;
1367 		if (copy_to_user(argp, &tr, sizeof tr))
1368 			goto out;
1369 		r = 0;
1370 		break;
1371 	}
1372 	case KVM_SET_GUEST_DEBUG: {
1373 		struct kvm_guest_debug dbg;
1374 
1375 		r = -EFAULT;
1376 		if (copy_from_user(&dbg, argp, sizeof dbg))
1377 			goto out;
1378 		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
1379 		if (r)
1380 			goto out;
1381 		r = 0;
1382 		break;
1383 	}
1384 	case KVM_SET_SIGNAL_MASK: {
1385 		struct kvm_signal_mask __user *sigmask_arg = argp;
1386 		struct kvm_signal_mask kvm_sigmask;
1387 		sigset_t sigset, *p;
1388 
1389 		p = NULL;
1390 		if (argp) {
1391 			r = -EFAULT;
1392 			if (copy_from_user(&kvm_sigmask, argp,
1393 					   sizeof kvm_sigmask))
1394 				goto out;
1395 			r = -EINVAL;
1396 			if (kvm_sigmask.len != sizeof sigset)
1397 				goto out;
1398 			r = -EFAULT;
1399 			if (copy_from_user(&sigset, sigmask_arg->sigset,
1400 					   sizeof sigset))
1401 				goto out;
1402 			p = &sigset;
1403 		}
1404 		r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
1405 		break;
1406 	}
1407 	case KVM_GET_FPU: {
1408 		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1409 		r = -ENOMEM;
1410 		if (!fpu)
1411 			goto out;
1412 		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
1413 		if (r)
1414 			goto out;
1415 		r = -EFAULT;
1416 		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
1417 			goto out;
1418 		r = 0;
1419 		break;
1420 	}
1421 	case KVM_SET_FPU: {
1422 		fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
1423 		r = -ENOMEM;
1424 		if (!fpu)
1425 			goto out;
1426 		r = -EFAULT;
1427 		if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
1428 			goto out;
1429 		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
1430 		if (r)
1431 			goto out;
1432 		r = 0;
1433 		break;
1434 	}
1435 	default:
1436 		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
1437 	}
1438 out:
1439 	kfree(fpu);
1440 	kfree(kvm_sregs);
1441 	return r;
1442 }
1443 
1444 static long kvm_vm_ioctl(struct file *filp,
1445 			   unsigned int ioctl, unsigned long arg)
1446 {
1447 	struct kvm *kvm = filp->private_data;
1448 	void __user *argp = (void __user *)arg;
1449 	int r;
1450 
1451 	if (kvm->mm != current->mm)
1452 		return -EIO;
1453 	switch (ioctl) {
1454 	case KVM_CREATE_VCPU:
1455 		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
1456 		if (r < 0)
1457 			goto out;
1458 		break;
1459 	case KVM_SET_USER_MEMORY_REGION: {
1460 		struct kvm_userspace_memory_region kvm_userspace_mem;
1461 
1462 		r = -EFAULT;
1463 		if (copy_from_user(&kvm_userspace_mem, argp,
1464 						sizeof kvm_userspace_mem))
1465 			goto out;
1466 
1467 		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
1468 		if (r)
1469 			goto out;
1470 		break;
1471 	}
1472 	case KVM_GET_DIRTY_LOG: {
1473 		struct kvm_dirty_log log;
1474 
1475 		r = -EFAULT;
1476 		if (copy_from_user(&log, argp, sizeof log))
1477 			goto out;
1478 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1479 		if (r)
1480 			goto out;
1481 		break;
1482 	}
1483 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1484 	case KVM_REGISTER_COALESCED_MMIO: {
1485 		struct kvm_coalesced_mmio_zone zone;
1486 		r = -EFAULT;
1487 		if (copy_from_user(&zone, argp, sizeof zone))
1488 			goto out;
1489 		r = -ENXIO;
1490 		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
1491 		if (r)
1492 			goto out;
1493 		r = 0;
1494 		break;
1495 	}
1496 	case KVM_UNREGISTER_COALESCED_MMIO: {
1497 		struct kvm_coalesced_mmio_zone zone;
1498 		r = -EFAULT;
1499 		if (copy_from_user(&zone, argp, sizeof zone))
1500 			goto out;
1501 		r = -ENXIO;
1502 		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
1503 		if (r)
1504 			goto out;
1505 		r = 0;
1506 		break;
1507 	}
1508 #endif
1509 	case KVM_IRQFD: {
1510 		struct kvm_irqfd data;
1511 
1512 		r = -EFAULT;
1513 		if (copy_from_user(&data, argp, sizeof data))
1514 			goto out;
1515 		r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
1516 		break;
1517 	}
1518 	case KVM_IOEVENTFD: {
1519 		struct kvm_ioeventfd data;
1520 
1521 		r = -EFAULT;
1522 		if (copy_from_user(&data, argp, sizeof data))
1523 			goto out;
1524 		r = kvm_ioeventfd(kvm, &data);
1525 		break;
1526 	}
1527 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1528 	case KVM_SET_BOOT_CPU_ID:
1529 		r = 0;
1530 		mutex_lock(&kvm->lock);
1531 		if (atomic_read(&kvm->online_vcpus) != 0)
1532 			r = -EBUSY;
1533 		else
1534 			kvm->bsp_vcpu_id = arg;
1535 		mutex_unlock(&kvm->lock);
1536 		break;
1537 #endif
1538 	default:
1539 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
1540 		if (r == -ENOTTY)
1541 			r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
1542 	}
1543 out:
1544 	return r;
1545 }
1546 
1547 #ifdef CONFIG_COMPAT
1548 struct compat_kvm_dirty_log {
1549 	__u32 slot;
1550 	__u32 padding1;
1551 	union {
1552 		compat_uptr_t dirty_bitmap; /* one bit per page */
1553 		__u64 padding2;
1554 	};
1555 };
1556 
1557 static long kvm_vm_compat_ioctl(struct file *filp,
1558 			   unsigned int ioctl, unsigned long arg)
1559 {
1560 	struct kvm *kvm = filp->private_data;
1561 	int r;
1562 
1563 	if (kvm->mm != current->mm)
1564 		return -EIO;
1565 	switch (ioctl) {
1566 	case KVM_GET_DIRTY_LOG: {
1567 		struct compat_kvm_dirty_log compat_log;
1568 		struct kvm_dirty_log log;
1569 
1570 		r = -EFAULT;
1571 		if (copy_from_user(&compat_log, (void __user *)arg,
1572 				   sizeof(compat_log)))
1573 			goto out;
1574 		log.slot	 = compat_log.slot;
1575 		log.padding1	 = compat_log.padding1;
1576 		log.padding2	 = compat_log.padding2;
1577 		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
1578 
1579 		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
1580 		if (r)
1581 			goto out;
1582 		break;
1583 	}
1584 	default:
1585 		r = kvm_vm_ioctl(filp, ioctl, arg);
1586 	}
1587 
1588 out:
1589 	return r;
1590 }
1591 #endif
1592 
1593 static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1594 {
1595 	struct page *page[1];
1596 	unsigned long addr;
1597 	int npages;
1598 	gfn_t gfn = vmf->pgoff;
1599 	struct kvm *kvm = vma->vm_file->private_data;
1600 
1601 	addr = gfn_to_hva(kvm, gfn);
1602 	if (kvm_is_error_hva(addr))
1603 		return VM_FAULT_SIGBUS;
1604 
1605 	npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
1606 				NULL);
1607 	if (unlikely(npages != 1))
1608 		return VM_FAULT_SIGBUS;
1609 
1610 	vmf->page = page[0];
1611 	return 0;
1612 }
1613 
1614 static const struct vm_operations_struct kvm_vm_vm_ops = {
1615 	.fault = kvm_vm_fault,
1616 };
1617 
1618 static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
1619 {
1620 	vma->vm_ops = &kvm_vm_vm_ops;
1621 	return 0;
1622 }
1623 
1624 static struct file_operations kvm_vm_fops = {
1625 	.release        = kvm_vm_release,
1626 	.unlocked_ioctl = kvm_vm_ioctl,
1627 #ifdef CONFIG_COMPAT
1628 	.compat_ioctl   = kvm_vm_compat_ioctl,
1629 #endif
1630 	.mmap           = kvm_vm_mmap,
1631 };
1632 
1633 static int kvm_dev_ioctl_create_vm(void)
1634 {
1635 	int fd;
1636 	struct kvm *kvm;
1637 
1638 	kvm = kvm_create_vm();
1639 	if (IS_ERR(kvm))
1640 		return PTR_ERR(kvm);
1641 	fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, 0);
1642 	if (fd < 0)
1643 		kvm_put_kvm(kvm);
1644 
1645 	return fd;
1646 }
1647 
1648 static long kvm_dev_ioctl_check_extension_generic(long arg)
1649 {
1650 	switch (arg) {
1651 	case KVM_CAP_USER_MEMORY:
1652 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
1653 	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
1654 #ifdef CONFIG_KVM_APIC_ARCHITECTURE
1655 	case KVM_CAP_SET_BOOT_CPU_ID:
1656 #endif
1657 	case KVM_CAP_INTERNAL_ERROR_DATA:
1658 		return 1;
1659 #ifdef CONFIG_HAVE_KVM_IRQCHIP
1660 	case KVM_CAP_IRQ_ROUTING:
1661 		return KVM_MAX_IRQ_ROUTES;
1662 #endif
1663 	default:
1664 		break;
1665 	}
1666 	return kvm_dev_ioctl_check_extension(arg);
1667 }
1668 
1669 static long kvm_dev_ioctl(struct file *filp,
1670 			  unsigned int ioctl, unsigned long arg)
1671 {
1672 	long r = -EINVAL;
1673 
1674 	switch (ioctl) {
1675 	case KVM_GET_API_VERSION:
1676 		r = -EINVAL;
1677 		if (arg)
1678 			goto out;
1679 		r = KVM_API_VERSION;
1680 		break;
1681 	case KVM_CREATE_VM:
1682 		r = -EINVAL;
1683 		if (arg)
1684 			goto out;
1685 		r = kvm_dev_ioctl_create_vm();
1686 		break;
1687 	case KVM_CHECK_EXTENSION:
1688 		r = kvm_dev_ioctl_check_extension_generic(arg);
1689 		break;
1690 	case KVM_GET_VCPU_MMAP_SIZE:
1691 		r = -EINVAL;
1692 		if (arg)
1693 			goto out;
1694 		r = PAGE_SIZE;     /* struct kvm_run */
1695 #ifdef CONFIG_X86
1696 		r += PAGE_SIZE;    /* pio data page */
1697 #endif
1698 #ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
1699 		r += PAGE_SIZE;    /* coalesced mmio ring page */
1700 #endif
1701 		break;
1702 	case KVM_TRACE_ENABLE:
1703 	case KVM_TRACE_PAUSE:
1704 	case KVM_TRACE_DISABLE:
1705 		r = -EOPNOTSUPP;
1706 		break;
1707 	default:
1708 		return kvm_arch_dev_ioctl(filp, ioctl, arg);
1709 	}
1710 out:
1711 	return r;
1712 }
1713 
1714 static struct file_operations kvm_chardev_ops = {
1715 	.unlocked_ioctl = kvm_dev_ioctl,
1716 	.compat_ioctl   = kvm_dev_ioctl,
1717 };
1718 
1719 static struct miscdevice kvm_dev = {
1720 	KVM_MINOR,
1721 	"kvm",
1722 	&kvm_chardev_ops,
1723 };
1724 
1725 static void hardware_enable(void *junk)
1726 {
1727 	int cpu = raw_smp_processor_id();
1728 	int r;
1729 
1730 	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
1731 		return;
1732 
1733 	cpumask_set_cpu(cpu, cpus_hardware_enabled);
1734 
1735 	r = kvm_arch_hardware_enable(NULL);
1736 
1737 	if (r) {
1738 		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
1739 		atomic_inc(&hardware_enable_failed);
1740 		printk(KERN_INFO "kvm: enabling virtualization on "
1741 				 "CPU%d failed\n", cpu);
1742 	}
1743 }
1744 
1745 static void hardware_disable(void *junk)
1746 {
1747 	int cpu = raw_smp_processor_id();
1748 
1749 	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
1750 		return;
1751 	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
1752 	kvm_arch_hardware_disable(NULL);
1753 }
1754 
1755 static void hardware_disable_all_nolock(void)
1756 {
1757 	BUG_ON(!kvm_usage_count);
1758 
1759 	kvm_usage_count--;
1760 	if (!kvm_usage_count)
1761 		on_each_cpu(hardware_disable, NULL, 1);
1762 }
1763 
1764 static void hardware_disable_all(void)
1765 {
1766 	spin_lock(&kvm_lock);
1767 	hardware_disable_all_nolock();
1768 	spin_unlock(&kvm_lock);
1769 }
1770 
1771 static int hardware_enable_all(void)
1772 {
1773 	int r = 0;
1774 
1775 	spin_lock(&kvm_lock);
1776 
1777 	kvm_usage_count++;
1778 	if (kvm_usage_count == 1) {
1779 		atomic_set(&hardware_enable_failed, 0);
1780 		on_each_cpu(hardware_enable, NULL, 1);
1781 
1782 		if (atomic_read(&hardware_enable_failed)) {
1783 			hardware_disable_all_nolock();
1784 			r = -EBUSY;
1785 		}
1786 	}
1787 
1788 	spin_unlock(&kvm_lock);
1789 
1790 	return r;
1791 }
1792 
1793 static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
1794 			   void *v)
1795 {
1796 	int cpu = (long)v;
1797 
1798 	if (!kvm_usage_count)
1799 		return NOTIFY_OK;
1800 
1801 	val &= ~CPU_TASKS_FROZEN;
1802 	switch (val) {
1803 	case CPU_DYING:
1804 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1805 		       cpu);
1806 		hardware_disable(NULL);
1807 		break;
1808 	case CPU_UP_CANCELED:
1809 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
1810 		       cpu);
1811 		smp_call_function_single(cpu, hardware_disable, NULL, 1);
1812 		break;
1813 	case CPU_ONLINE:
1814 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
1815 		       cpu);
1816 		smp_call_function_single(cpu, hardware_enable, NULL, 1);
1817 		break;
1818 	}
1819 	return NOTIFY_OK;
1820 }
1821 
1822 
1823 asmlinkage void kvm_handle_fault_on_reboot(void)
1824 {
1825 	if (kvm_rebooting)
1826 		/* spin while reset goes on */
1827 		while (true)
1828 			;
1829 	/* Fault while not rebooting.  We want the trace. */
1830 	BUG();
1831 }
1832 EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
1833 
1834 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
1835 		      void *v)
1836 {
1837 	/*
1838 	 * Some (well, at least mine) BIOSes hang on reboot if
1839 	 * in vmx root mode.
1840 	 *
1841 	 * And Intel TXT required VMX off for all cpu when system shutdown.
1842 	 */
1843 	printk(KERN_INFO "kvm: exiting hardware virtualization\n");
1844 	kvm_rebooting = true;
1845 	on_each_cpu(hardware_disable, NULL, 1);
1846 	return NOTIFY_OK;
1847 }
1848 
1849 static struct notifier_block kvm_reboot_notifier = {
1850 	.notifier_call = kvm_reboot,
1851 	.priority = 0,
1852 };
1853 
1854 void kvm_io_bus_init(struct kvm_io_bus *bus)
1855 {
1856 	memset(bus, 0, sizeof(*bus));
1857 }
1858 
1859 void kvm_io_bus_destroy(struct kvm_io_bus *bus)
1860 {
1861 	int i;
1862 
1863 	for (i = 0; i < bus->dev_count; i++) {
1864 		struct kvm_io_device *pos = bus->devs[i];
1865 
1866 		kvm_iodevice_destructor(pos);
1867 	}
1868 }
1869 
1870 /* kvm_io_bus_write - called under kvm->slots_lock */
1871 int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr,
1872 		     int len, const void *val)
1873 {
1874 	int i;
1875 	for (i = 0; i < bus->dev_count; i++)
1876 		if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
1877 			return 0;
1878 	return -EOPNOTSUPP;
1879 }
1880 
1881 /* kvm_io_bus_read - called under kvm->slots_lock */
1882 int kvm_io_bus_read(struct kvm_io_bus *bus, gpa_t addr, int len, void *val)
1883 {
1884 	int i;
1885 	for (i = 0; i < bus->dev_count; i++)
1886 		if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
1887 			return 0;
1888 	return -EOPNOTSUPP;
1889 }
1890 
1891 int kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
1892 			     struct kvm_io_device *dev)
1893 {
1894 	int ret;
1895 
1896 	down_write(&kvm->slots_lock);
1897 	ret = __kvm_io_bus_register_dev(bus, dev);
1898 	up_write(&kvm->slots_lock);
1899 
1900 	return ret;
1901 }
1902 
1903 /* An unlocked version. Caller must have write lock on slots_lock. */
1904 int __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
1905 			      struct kvm_io_device *dev)
1906 {
1907 	if (bus->dev_count > NR_IOBUS_DEVS-1)
1908 		return -ENOSPC;
1909 
1910 	bus->devs[bus->dev_count++] = dev;
1911 
1912 	return 0;
1913 }
1914 
1915 void kvm_io_bus_unregister_dev(struct kvm *kvm,
1916 			       struct kvm_io_bus *bus,
1917 			       struct kvm_io_device *dev)
1918 {
1919 	down_write(&kvm->slots_lock);
1920 	__kvm_io_bus_unregister_dev(bus, dev);
1921 	up_write(&kvm->slots_lock);
1922 }
1923 
1924 /* An unlocked version. Caller must have write lock on slots_lock. */
1925 void __kvm_io_bus_unregister_dev(struct kvm_io_bus *bus,
1926 				 struct kvm_io_device *dev)
1927 {
1928 	int i;
1929 
1930 	for (i = 0; i < bus->dev_count; i++)
1931 		if (bus->devs[i] == dev) {
1932 			bus->devs[i] = bus->devs[--bus->dev_count];
1933 			break;
1934 		}
1935 }
1936 
1937 static struct notifier_block kvm_cpu_notifier = {
1938 	.notifier_call = kvm_cpu_hotplug,
1939 	.priority = 20, /* must be > scheduler priority */
1940 };
1941 
1942 static int vm_stat_get(void *_offset, u64 *val)
1943 {
1944 	unsigned offset = (long)_offset;
1945 	struct kvm *kvm;
1946 
1947 	*val = 0;
1948 	spin_lock(&kvm_lock);
1949 	list_for_each_entry(kvm, &vm_list, vm_list)
1950 		*val += *(u32 *)((void *)kvm + offset);
1951 	spin_unlock(&kvm_lock);
1952 	return 0;
1953 }
1954 
1955 DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
1956 
1957 static int vcpu_stat_get(void *_offset, u64 *val)
1958 {
1959 	unsigned offset = (long)_offset;
1960 	struct kvm *kvm;
1961 	struct kvm_vcpu *vcpu;
1962 	int i;
1963 
1964 	*val = 0;
1965 	spin_lock(&kvm_lock);
1966 	list_for_each_entry(kvm, &vm_list, vm_list)
1967 		kvm_for_each_vcpu(i, vcpu, kvm)
1968 			*val += *(u32 *)((void *)vcpu + offset);
1969 
1970 	spin_unlock(&kvm_lock);
1971 	return 0;
1972 }
1973 
1974 DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
1975 
1976 static const struct file_operations *stat_fops[] = {
1977 	[KVM_STAT_VCPU] = &vcpu_stat_fops,
1978 	[KVM_STAT_VM]   = &vm_stat_fops,
1979 };
1980 
1981 static void kvm_init_debug(void)
1982 {
1983 	struct kvm_stats_debugfs_item *p;
1984 
1985 	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
1986 	for (p = debugfs_entries; p->name; ++p)
1987 		p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
1988 						(void *)(long)p->offset,
1989 						stat_fops[p->kind]);
1990 }
1991 
1992 static void kvm_exit_debug(void)
1993 {
1994 	struct kvm_stats_debugfs_item *p;
1995 
1996 	for (p = debugfs_entries; p->name; ++p)
1997 		debugfs_remove(p->dentry);
1998 	debugfs_remove(kvm_debugfs_dir);
1999 }
2000 
2001 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
2002 {
2003 	if (kvm_usage_count)
2004 		hardware_disable(NULL);
2005 	return 0;
2006 }
2007 
2008 static int kvm_resume(struct sys_device *dev)
2009 {
2010 	if (kvm_usage_count)
2011 		hardware_enable(NULL);
2012 	return 0;
2013 }
2014 
2015 static struct sysdev_class kvm_sysdev_class = {
2016 	.name = "kvm",
2017 	.suspend = kvm_suspend,
2018 	.resume = kvm_resume,
2019 };
2020 
2021 static struct sys_device kvm_sysdev = {
2022 	.id = 0,
2023 	.cls = &kvm_sysdev_class,
2024 };
2025 
2026 struct page *bad_page;
2027 pfn_t bad_pfn;
2028 
2029 static inline
2030 struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
2031 {
2032 	return container_of(pn, struct kvm_vcpu, preempt_notifier);
2033 }
2034 
2035 static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
2036 {
2037 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2038 
2039 	kvm_arch_vcpu_load(vcpu, cpu);
2040 }
2041 
2042 static void kvm_sched_out(struct preempt_notifier *pn,
2043 			  struct task_struct *next)
2044 {
2045 	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
2046 
2047 	kvm_arch_vcpu_put(vcpu);
2048 }
2049 
2050 int kvm_init(void *opaque, unsigned int vcpu_size,
2051 		  struct module *module)
2052 {
2053 	int r;
2054 	int cpu;
2055 
2056 	r = kvm_arch_init(opaque);
2057 	if (r)
2058 		goto out_fail;
2059 
2060 	bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
2061 
2062 	if (bad_page == NULL) {
2063 		r = -ENOMEM;
2064 		goto out;
2065 	}
2066 
2067 	bad_pfn = page_to_pfn(bad_page);
2068 
2069 	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
2070 		r = -ENOMEM;
2071 		goto out_free_0;
2072 	}
2073 
2074 	r = kvm_arch_hardware_setup();
2075 	if (r < 0)
2076 		goto out_free_0a;
2077 
2078 	for_each_online_cpu(cpu) {
2079 		smp_call_function_single(cpu,
2080 				kvm_arch_check_processor_compat,
2081 				&r, 1);
2082 		if (r < 0)
2083 			goto out_free_1;
2084 	}
2085 
2086 	r = register_cpu_notifier(&kvm_cpu_notifier);
2087 	if (r)
2088 		goto out_free_2;
2089 	register_reboot_notifier(&kvm_reboot_notifier);
2090 
2091 	r = sysdev_class_register(&kvm_sysdev_class);
2092 	if (r)
2093 		goto out_free_3;
2094 
2095 	r = sysdev_register(&kvm_sysdev);
2096 	if (r)
2097 		goto out_free_4;
2098 
2099 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
2100 	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
2101 					   __alignof__(struct kvm_vcpu),
2102 					   0, NULL);
2103 	if (!kvm_vcpu_cache) {
2104 		r = -ENOMEM;
2105 		goto out_free_5;
2106 	}
2107 
2108 	kvm_chardev_ops.owner = module;
2109 	kvm_vm_fops.owner = module;
2110 	kvm_vcpu_fops.owner = module;
2111 
2112 	r = misc_register(&kvm_dev);
2113 	if (r) {
2114 		printk(KERN_ERR "kvm: misc device register failed\n");
2115 		goto out_free;
2116 	}
2117 
2118 	kvm_preempt_ops.sched_in = kvm_sched_in;
2119 	kvm_preempt_ops.sched_out = kvm_sched_out;
2120 
2121 	kvm_init_debug();
2122 
2123 	return 0;
2124 
2125 out_free:
2126 	kmem_cache_destroy(kvm_vcpu_cache);
2127 out_free_5:
2128 	sysdev_unregister(&kvm_sysdev);
2129 out_free_4:
2130 	sysdev_class_unregister(&kvm_sysdev_class);
2131 out_free_3:
2132 	unregister_reboot_notifier(&kvm_reboot_notifier);
2133 	unregister_cpu_notifier(&kvm_cpu_notifier);
2134 out_free_2:
2135 out_free_1:
2136 	kvm_arch_hardware_unsetup();
2137 out_free_0a:
2138 	free_cpumask_var(cpus_hardware_enabled);
2139 out_free_0:
2140 	__free_page(bad_page);
2141 out:
2142 	kvm_arch_exit();
2143 out_fail:
2144 	return r;
2145 }
2146 EXPORT_SYMBOL_GPL(kvm_init);
2147 
2148 void kvm_exit(void)
2149 {
2150 	tracepoint_synchronize_unregister();
2151 	kvm_exit_debug();
2152 	misc_deregister(&kvm_dev);
2153 	kmem_cache_destroy(kvm_vcpu_cache);
2154 	sysdev_unregister(&kvm_sysdev);
2155 	sysdev_class_unregister(&kvm_sysdev_class);
2156 	unregister_reboot_notifier(&kvm_reboot_notifier);
2157 	unregister_cpu_notifier(&kvm_cpu_notifier);
2158 	on_each_cpu(hardware_disable, NULL, 1);
2159 	kvm_arch_hardware_unsetup();
2160 	kvm_arch_exit();
2161 	free_cpumask_var(cpus_hardware_enabled);
2162 	__free_page(bad_page);
2163 }
2164 EXPORT_SYMBOL_GPL(kvm_exit);
2165